public function oauth_callback()
 {
     $service = Oauth_Service::get_service_by_name($_GET['service']);
     if ($service) {
         try {
             /* initialize the Callback */
             $cb = new WPOF_Callback($service->get_submenu_slug(), $service->get_client_config(), $service->get_token_storage(), new Guzzle3Client());
             /* handle the callback */
             $access_token = $cb->handleCallback($_GET);
             $service->handle_access_token($access_token);
         } catch (\Exception $e) {
             $this->redirect_to_login_url_with_error(self::CONFIGURATION_ERROR, $_GET['service']);
         }
     } else {
         echo 'No script kiddies';
         die;
     }
 }
 public static function get_wpof_login_count($service_name)
 {
     $service = Oauth_Service::get_service_by_name($service_name);
     return (int) get_option(self::META_PREFIX . $service->get_submenu_slug());
 }